High IL-32 expression is associated with osteolytic bone disease. (A) IL32 gene expression in MM cells from patients without bone disease (BD; median, 0.42; n = 36) compared with patients with BD (median, 0.53; n = 137). Data obtained from GSE755. BD was defined as having ≥1 osteolytic lesion as assessed by magnetic resonance imaging. Mann-Whitney U test P < .001. (B) Summary of main findings presented in the article. In response to hypoxia, MM cells secrete IL-32 in EVs, which promote osteoclast differentiation.